# Old Second Bancorp Inc (OSBC) SEC filings and CIK

Canonical: https://sec-api.dev/companies/osbc

> OSBC’s SEC CIK is 0000357173 (357173).

Insider transactions in the latest quarter: 15 (0 purchases, 7 sales). https://sec-api.dev/insider-trading/osbc

| Filed | Form | Filing |
| --- | --- | --- |
| 2026-10-30 | SCHEDULE 13G | https://www.sec.gov/Archives/edgar/data/357173/000210011926001679/0002100119-26-001679-index.htm |

API: GET https://sec-api.dev/api/v1/filings?cik=357173

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